I use a bullet smoker for turkeys up to about 16-18 lbs.
I brine them at least 12 hours, it does improve the juicyness by lenghtening the protein molecules and allowing the turkey to soak up some of the brine. For brine I use a 5 gallon bucket, H2O to cover (about 2.5 gal), enough non-iodized salt in the H2O to float a raw egg, and an amount of brown sugar to equal the sugar.
I put the turkey in about 8 hours prior to wanting to eat it. I use an electric smoker so I use wood chips (usually a mixture of cherry and apple) in a Marie Callendars pie pan covered with foil and holes punched in the foil on top of the lava rocks. That will smoke for 2-3 hours and then I switch it out with another pan of wood.
In the H2O pan I put water, green onions split lengthways, whole garlic cloves and a handful of parsley.
About an hour before I am going to start the turkey I set it out so it can dry and the sugar makes a very thin coating.
It goes in the smoker, on the top rack and gets left alone for at least 3 hours. I change the wood chips and start checking the turkey at about the 5 hour mark. It will get very dark because of the sugar, if you don't want that, try covering with foil. Keep the "I have to look and see how it is doing" checks to a minimum, you don't want to lose the heat in the smoker by taking the lid off a lot.
At about the 6 hour mark you can start checking doneness with an instant read thermometer in the thigh. When it gets done, set inside, covered with foil for 30 minutes or so and let it rest.
Carve and enjoy.
bob